Improvement in sliding drop-lights for chandeliers



B. THACKARA.

Sliding Drop-Lights for Chandeliers. 110,151,171, PatentedMay19,1874.

lMFl/aM-l/THMMFl/lt' LzzAl. X (nan/7111532500559 Unrrnn STATES PATENT @FFIon.

BENJAll [IN THAOKARA, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNORTO HIMSELF, l VILLIAM J. BUCK, JOHN H. SOUTHVVORTH, CHARLES THAOK- ARA, AND BYRON H. BUCK, OF SAME PLACE.

IMPROVEMENT IN SLIDING DROP-LIGHTS FOR CHANDELIERS.

Specification forming part of Letters Patent No. 151,171, dated May 19, 1874 application filed April 23, 1874.

To all whom it may concern:

Be it known that I, BENJAMIN THAGKARA,

of Philadelphia, Pennsylvania, have invented burners are fixed and one or more are connected to a vertically-adjustable sliding tube;

and the object of my invention is to accurately balance and guide the said sliding tube so that it will retain the position to which it maybe adjusted, and so that it will slide in a direct course parallel with the fixed tube.

This object I attain by the employment, in connection with the cords A A, which support the drop-light tube E of a spring-fusee, B, shown in the side view, Figure l, of the accompanying drawing, the force exerted by the spring, through the said fusee, on the cord being uniform, or nearly so, owing to the decreasing power of the spring, as it is uncoiled, being compensated for by an increased leverage.

The two suspension-cords are directed to the same tangential point on the fusee, and are wound round and unwound from the same simultaneously, so that precisely the same movement may be imparted to both cords, a direct sliding of the drop-light tube being thereby insured.

D is a portion of the fixed tube of a chandelier, and E part of the internal adjustable tube, to which is secured a cross-bar, G; and to the ends of the latter are attached the suspension-cords A and A, and which are directed, by pulleys, in the manner described hereafter, to the fusee B, both cords being attached to the latter. This fusee consists of a casing, the lower cylindrical portion of which contains the usual coiled spring, one end of the latter being secured to the fixed tube D, and the other to the fusce, on the groove of the fusee, and the cord A passing upward and over the pulleys a and b, hung to the same frame H, and thence to the groove .of the fusee.

On pulling down the sliding tube E the spring will be wound up, and will tend, when the tube is released, to move the fuse-e in the direction of the arrow, Fig. 1.

As the spring becomes gradually uncoiled, its force as gradually diminishes, but, to compensate for this diminution of force, it is ex- 7 erted to elevate the tube through a constantlydecreasing leverage, owing to the cords being in g wound round a fusee which gradually decreases in diameter; but the spring is so regulated as to balance the tube E and its burin ers, and this it will (10,110 matter what the position of the tube may be, as the power exerted by thespring on the cords, through the medium of the fusee, is always thesame, or nearly so.

In order to avail myself of this equalizet balancing effect of the spring-fusee, I direct to the same the two cords, in the manner illustrated in the drawing, both cords coming in contact with the fusee at the same tangential point and being wound round and unwound from the fusee simultaneously.

The advantage of this arrangement will be best understood by supposing the guidingpulleys b b to be absent, and the cords to be directed to the fusee in the the manner illustrated by dotted lines in Fig. 2, where the cords reach the fusee at opposite tangential points.

In this case the cords would not traverse at the same speed and would not exert equal them downward, at each side of the fnsee, to the sliding tube, all as set forth.

In testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses.

BENJAMIN TH AOKARA.

Witnesses:

WM. A. STEEL, HARRY SMITH. 

